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A Salas

Publications and source records attributed to A Salas.

At least 55 records · Page 3Linked to original sources
PubMed2001

Small cell carcinoma of the kidney: a case report and review of the literature.

Small cell carcinoma is a malignant tumor composed of small cells with a diffuse growth pattern. It has immunohistochemical and ultrastructural features of both neuroendocrine and epithelial neoplasms. These tumors constitute 10% to 20% of malignant tumors in the lung, which is their most frequent site. They have been described in other extrapulmonary sites, where they are defined using the same criteria as used in the lung. These tumors are rarely found in the genitourinary tract. Fewer than 30 cases have been reported in the kidney. The differential diagnosis mainly includes other small round cell tumors and metastatic small cell lung carcinoma. We present and discuss a primary small cell carcinoma of the kidney (to our knowledge the 9th to be reported in the literature), which we studied with light microscopy, immunohistochemistry, electron microscopy, and, for the first time, flow cytometry.

Aged↗
PubMed2000

Molecular characterization of non-B HIV type 1 subtypes from Africa in Spain.

All of the known HIV-1 subtypes are present in sub-Saharan Africa. The B subtype is predominant in the United States and Europe, but previous studies have revealed that other subtypes are also in circulation. We report here on the genetic characterization of eight non-B subtype VIH-1 virus strains detected during 1999 in patients living in Spain and having epidemiological relationships with African countries. Five isolates clustering with recombinant form CRF02-AG came from West and Central Africa. One isolate was characterized as being of the D subtype in the gp41 region, and clustered with subtype A outside the CRF02-AG recombinant form, in regions C2V3 and p17. Another isolate was a G subtype, and the remaining isolate was an O subtype. In Spain, the B subtype is the most frequently detected HIV-1 subtype, although in more recent years non-B subtypes have been introduced through immigrant HIV-1-infected individuals coming from African countries, or through infected persons having relationships with endemically affected areas.

Africa↗
PubMed2000

H(2)O(2) and PARS mediate lung P-selectin upregulation in acute pancreatitis.

P-selectin and circulating xanthine oxidase are involved in the process of neutrophil infiltration into the lung associated with acute pancreatitis. This study investigated the mediators that trigger the upregulation of P-selectin in this process. Pancreatitis was induced in rats by intraductal administration of 5% sodium taurocholate. P-selectin expression was measured using radiolabeled antibodies. Neutrophil infiltration and PAF levels were also evaluated. The role of superoxide radical, H(2)O(2), or the enzyme poly (ADP-ribose) synthetase (PARS) on these processes was determined in groups of animals treated with the corresponding inhibitors. Pancreatitis was associated with an increase in P-selectin expression in the lung. Inhibition of PARS or H(2)O(2) abrogated P-selectin upregulation, PAF generation, and neutrophil recruitment. Superoxide dismutation prevented neutrophil recruitment and PAF generation, but had no effect on P-selectin expression. We conclude that during acute pancreatitis, upregulation of P-selectin in the pulmonary endothelium is triggered by H(2)O(2) and PARS activity.

Acute Disease↗
PubMed2000

Sequence variation of two hypervariable short tandem repeats at the D22S683 and D6S477 loci.

For two short tandem repeats at the D22S683 and D6S477 loci, 30 and 22 selected alleles, respectively were sequenced. A total of 20 different alleles were found for the D22S683 locus and 12 alleles for the D6S477 locus. In both systems the alleles were designated according to the total number of repeats. D22S683 is a hypervariable STR consisting of blocks of (TATC) repeats with a basic sequence structure (TATATC)n (TATC)n (ATC)0-1 (TATC)n. The D6S477 locus consists of blocks of (TCTA) repeats with a basic sequence structure (TCTA)n (TA)1 (TCTA)0-2 (TA)0-1 (TCTA)n. Population data showed a heterozygosity of 0.89 for D22S683 and 0.75 for D6S477. These STRs are promising markers for forensic genetics as they are robust and can be easily included in multiplexes.

Alleles↗
PubMed2000

Oleoyl-estrone induces the massive loss of body weight in Zucker fa/fa rats fed a high-energy hyperlipidic diet.

To test whether oleoyl-estrone plus a hyperlipidic diet affects body weight in Zucker fa/fa rats, 13-week-old male Zucker obese (fa/fa) rats initially weighing 440-470 g were used. They were fed for 15 days with a powdered hyperlipidic diet (16.97 MJ/kg metabolizable energy) in which 46.6% was lipid-derived and 16.1% was protein-derived energy and containing 1.23 +/- 0.39 µmol/kg of fatty-acyl esters of estrone. This diet was supplemented with added oleoyl-estrone to produce a diet with 33.3 µmol/kg of fatty-acyl estrone. Oral administration of oleoyl-estrone in a hyperlipidic diet (at a mean dose of 0.5 µmol. kg(-1).d(-1)) resulted in significant losses of fat, energy and, ultimately, weight. Treatment induced the maintenance of energy expenditure combined with lower food intake, creating an energy gap that was filled with internal fat stores while preserving body protein, in contrast with the marked growth of controls fed the hyperlipidic diet. Treatment of genetically obese rats with a hyperlipidic diet containing additional oleoyl-estrone resulted in the loss of fat reserves with scant modification of other metabolic parameters, except for lower plasma glucose and insulin levels. The results agree with the postulated role of oleoyl-estrone as a ponderostat signal.

Journal Article↗
PubMed2000

Validity of the hospital discharge diagnosis in epidemiologic studies of biliopancreatic pathology. PANKRAS II Study Group.

BACKGROUND: The aim was to analyse the magnitude, direction and predictors of change in the main hospital discharge diagnosis (HDD) after a clinical expert review, among patients included in a multicentre molecular epidemiologic study of biliopancreatic diseases. METHODS: A total of 602 patients with a suspicion diagnosis of pancreas cancer (PC), cancer of the extrahepatic biliary system (CEBS) or benign biliopancreatic pathologies (BPP) were prospectively recruited at five general hospitals. A structured form was used to collect information from medical records. A panel of experts revised all diagnostic information and established the main clinicopathological diagnosis (CPD) by consensus. RESULTS: Of the 204 cases with a HDD of PC, 176 (86%) were deemed to have a CPD of PC, eight of CEBS, twelve a neoplasm of different origin, four BPP and four syndromic diagnoses. Thus, 28 cases (14%) were false positives. Of the 129 patients with a HDD of CEBS, 15 (12%) were false positives. Nine of the 396 cases with a HDD of non-PC (2%) had a CPD of PC (false negatives), whilst 14 of 471 patients with a HDD of non-CEBS (3%) were deemed to have CEBS. Overall, sensitivity and specificity of HDD for PC were, respectively, 95 and 93%, and for CEBS, 89 and 97%. Cytohistological confirmation and laparotomy were independent predictors of diagnostic change. CONCLUSIONS: Validity of the HDD was high, but its association with some clinical variables suggests that sole reliance on HDD can significantly bias results, and highlights the need to review all HDDs. Alternatively, only patients at high risk of misdiagnosis could be reviewed: primarily, those lacking a cytohistological diagnosis or a laparotomy. No exclusions appear warranted solely on the basis of age, gender or tumour spread.

Aged↗
PubMed2000

VCAM-1, but not ICAM-1 or MAdCAM-1, immunoblockade ameliorates DSS-induced colitis in mice.

Adhesion molecule immunoneutralization is envisioned as a promising therapy for inflammatory bowel disease, but the relative value of selective blockade of different adhesion molecules has not been established. The aims of this study were to measure expression and functional relevance of endothelial intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and mucosal addressin cell adhesion molecule 1 (MAdCAM-1) in leukocyte recruitment in experimental colitis and to compare the therapeutic effectiveness of their selective blockade. For this purpose, cell adhesion molecule expression was measured by the dual radiolabeled antibody technique in mice with dextran sulfate sodium-induced colitis and controls. Leukocyte-endothelial cell interactions were determined in colonic venules by fluorescence intravital microscopy. Therapeutic effects of chronic treatment with anti-ICAM-1, anti-VCAM-1, or anti-MAdCAM-1 antibodies were also assessed. Whereas colonic endothelial ICAM-1 was constitutively expressed and had a mild up-regulation in colitic animals, constitutive expression of VCAM-1 and MAdCAM-1 was low, but markedly increased after induction of colitis. Leukocyte adhesion was abrogated by immunoneutralization of VCAM-1 or MAdCAM-1 but not by treatment with an anti-ICAM-1 antibody. Chronic administration of anti-VCAM-1 antibody, but not anti-ICAM-1 or anti-MAdCAM-1, resulted in significant attenuation of colitis in terms of disease activity index, colon length, ratio of colon weight to length, and myeloperoxidase activity. In conclusion, VCAM-1 plays a central role in leukocyte recruitment in colitis and blockade of this adhesion molecule has higher therapeutic effect than immunoneutralization of ICAM-1 or MAdCAM-1 in this experimental model.

Animals↗
PubMed2000

mtDNA hypervariable region II (HVII) sequences in human evolution studies.

Variation in human mitochondrial DNA (mtDNA) has been used to infer the origin and migration patterns in human populations. mtDNA analysis has been focused mainly on the first hypervariable region (HVI). Nevertheless, although many studies of the second hypervariable region (HVII) have been carried out during recent years, the correlation between the first and the second hypervariable regions has not been well established. We have analysed 71 individuals from a relatively isolated region at the westernmost edge of continental Europe (Galicia, NW Iberian peninsula) and we have used available HVII sequence information from another 17 European and African populations. The results show high concordance between the two hypervariable regions, not only in variability levels but also in other phylogenetic aspects. The study of the population structure through an AMOVA analysis shows a low level of heterogeneity in the European populations. Nevertheless, we have found some inconsistency in the results, which are related to the mutation rate in these two hypervariable regions. These results are compatible with a high heterogeneity of mutation rates across the HVII region and stress the interest of HVII in population and forensic genetics.

Base Sequence↗
PubMed2000

Tepoxalin inhibits inflammation and microvascular dysfunction induced by abdominal irradiation in rats.

BACKGROUND: Inflammatory cells contribute to the acute and sub-acute sequelae of radiation therapy. Tepoxalin, an inhibitor of cyclooxygenase and 5-lipoxygenase that suppresses NF-kappaB activation, has potent anti-inflammatory activity. AIMS: To assess the effects of tepoxalin on radiation-induced inflammatory damage, and determine its mechanisms of action. METHODS: Leucocyte rolling, adhesion and emigration, and albumin leakage were determined by intra-vital microscopy in rat mesenteric venules. NF-kappaB activation was measured by electrophoretic mobility shift assays, and endothelial intercellular adhesion molecule-1 expression by the radiolabelled antibody technique. Groups of irradiated rats were treated with tepoxalin, N-acetyl-L-cysteine, zileuton (lipoxygenase inhibitor), or vehicle. RESULTS: Irradiated animals had a marked increase in the number of rolling, adherent and emigrated leucocytes in mesenteric venules, and in microvascular permeability. Tepoxalin prevented leucocyte adhesion and the increase in permeability after radiation. Tepoxalin did not inhibit radiation-induced NF-kappaB activation or intercellular adhesion molecule-1 up-regulation, while N-acetyl-L-cysteine, which attenuated NF-kappaB activation, had no effect on leucocyte recruitment. In contrast, tepoxalin inhibited the increase in leukotriene B4 levels after radiation, and the anti-inflammatory effects of the drug were mimicked by zileuton. CONCLUSIONS: Tepoxalin affords significant protection against radiation-induced inflammation and microvascular dysfunction in splanchnic organs through a mechanism dependent on leukotriene synthesis inhibition.

Abdomen↗
PubMed2000

Surface hydrophobicity of the rat colonic mucosa is a defensive barrier against macromolecules and toxins.

BACKGROUND: Mucosal surface hydrophobicity is a key factor of the gastric acid defence barrier. In the colon, surface hydrophobicity is high but its biological function remains unexplored. AIMS: To investigate the functional changes of the barrier due to removal of the surface active phospholipid layer by a detergent, or to reinforcement of the surface active phospholipid by local application of a suspension of lipids. METHODS: Surface hydrophobicity (contact angle measurement), colonic permeability (lumen to blood clearance of mannitol and dextran), and mucosal resistance against luminal aggression (distal colitis induced by dextran sodium sulphate, DSS) were investigated in three study groups: (a) rats pretreated with a detergent (Brij 35) known to remove surfactant lipids; (b) rats pretreated with a suspension of surface active lipids (tripalmitin and dipalmitoyl-phosphatidylcholine); and (c) control rats pretreated with the corresponding vehicles. RESULTS: In controls, surface hydrophobicity was low on the caecal mucosa and high in colon and rectum. Detergent treatment reduced surface hydrophobicity, and increased colonic permeability to mannitol and dextran. Conversely, treatment with lipids increased surface hydrophobicity, and reduced colonic permeability. Administration of DSS induced a progressive loss of colonic surface hydrophobicity, and an increase in permeability to mannitol and dextran. Detergent treatment increased susceptibility to epithelial damage and mucosal inflammation by DSS. Treatment with lipids reduced susceptibility to DSS colitis. CONCLUSION: Colonic surface hydrophobicity modulates permeability to hydrophilic molecules and protects against toxins.

Animals↗
PubMed2000

Heparin attenuates TNF-alpha induced inflammatory response through a CD11b dependent mechanism.

BACKGROUND: In addition to its anticoagulant properties, heparin has anti-inflammatory effects, the molecular and mechanistic bases of which are incompletely defined. AIMS: The current studies were designed to test the hypothesis that heparin abrogates the expression or function of leucocyte-endothelial adherence molecules which are fundamental to the acute inflammatory response. METHODS: The effects of heparin on tumour necrosis factor alpha (TNF-alpha) induced leucocyte rolling, adhesion, and migration as well as vascular permeability were assessed in rat mesenteric venules using intravital microscopy. Expression of adhesion molecules was quantitated using a double radiolabelled monoclonal antibody (mAb) binding technique in vivo (P-selectin, intercellular cell adhesion molecule type 1 (ICAM-1), and vascular cell adhesion molecule 1 (VCAM-1)) or flow cytometry (CD11a, CD11b, and L-selectin). Ex vivo binding of heparin to neutrophils was assessed by flow cytometry. RESULTS: TNF-alpha induced a significant increase in leucocyte rolling, adhesion, and migration, and vascular permeability, coincident with a significant increase in expression of P-selectin, ICAM-1, and VCAM-1. Ex vivo assessment of blood neutrophils showed significant upregulation of CD11a and CD11b and significant downregulation of L-selectin within five hours of TNF-alpha administration. Heparin pretreatment significantly attenuated leucocyte rolling, adhesion, and migration but did not affect expression of cell adhesion molecules or vascular permeability elicited by TNF-alpha administration. Binding of heparin was significantly increased on blood neutrophils obtained five hours after TNF-alpha administration. Preincubation with an anti-CD11b mAb but not with an anti-CD11a or anti-L-selectin antibody significantly diminished heparin binding ex vivo. CONCLUSIONS: Our results support the concept that the anti-inflammatory effects of heparin involve attenuation of a CD11b dependent adherent mechanism.

Animals↗
PubMed2000

Ethical-legal problems of DNA databases in criminal investigation.

Advances in DNA technology and the discovery of DNA polymorphisms have permitted the creation of DNA databases of individuals for the purpose of criminal investigation. Many ethical and legal problems arise in the preparation of a DNA database, and these problems are especially important when one analyses the legal regulations on the subject. In this paper three main groups of possibilities, three systems, are analysed in relation to databases. The first system is based on a general analysis of the population; the second one is based on the taking of samples for a particular list of crimes, and a third is based only on the specific analysis of each case. The advantages and disadvantages of each system are compared and controversial issues are then examined. We found the second system to be the best choice for Spain and other European countries with a similar tradition when we weighed the rights of an individual against the public's interest in the prosecution of a crime.

Civil Rights↗
PubMed1999

Influence of dose-rate on inflammatory damage and adhesion molecule expression after abdominal radiation in the rat.

PURPOSE: The goal of this study was to assess the effects of two clinically relevant radiation dose-rates on endothelial adhesion molecule expression, inflammatory response, and microvascular dysfunction. METHODS AND MATERIALS: Rats were irradiated with 10 Gy at low (0.9 Gy/min) or high (3 Gy/min) dose-rates. Control animals received sham irradiation. Leukocyte rolling, adhesion, emigration, and microvascular permeability were assessed in mesenteric venules by intravital microscopy 6 hours after irradiation. P-selectin and intercellular adhesion molecule-1 (ICAM-1) expression were measured using radiolabeled monoclonal antibodies. RESULTS: Low dose-rate (LDR) abdominal irradiation increased leukocyte adhesion compared with sham-irradiated animals, whereas high dose-rate (HDR) irradiation resulted in enhanced leukocyte rolling, adhesion, and emigration, compared with the LDR or with sham-irradiated rats. Both dose-rates increased microvascular permeability, although this effect was significantly greater after radiation with the high (8-fold) than the low (5-fold) dose-rate. HDR radiation induced significantly larger increments in P-selectin expression in splanchnic organs than LDR, whereas in most organs ICAM-1 expression was only upregulated by the HDR. Blockade of ICAM-1, but not P-selectin, abrogated leukocyte adhesion at both dose-rates. CONCLUSIONS: The magnitude of upregulation of endothelial adhesion molecules, leukocyte recruitment, and endothelial barrier dysfunction elicited by radiation therapy is dependent on the dose-rate at which the radiation is delivered.

Abdomen↗
PubMed1999

Treatment of visceral leishmaniasis in HIV-infected patients: a randomized trial comparing meglumine antimoniate with amphotericin B. Spanish HIV-Leishmania Study Group.

BACKGROUND: Visceral leishmaniasis is common in patients with HIV infection living in endemic areas, but the most effective and safe treatment remains unknown. OBJECTIVE: To compare the efficacy and safety of meglumine antimoniate versus amphotericin B in HIV-infected patients with first episodes of visceral leishmaniasis (VL). DESIGN: An open, multicentre, prospective and randomized trial. SETTING: Twelve tertiary hospitals. PATIENTS: Eighty-nine consecutive HIV-infected patients diagnosed with VL. Patients were randomly assigned to treatment with either meglumine antimoniate (20 mg pentavalent antimony per kilogram of body weight per day) or amphotericin B (0.7 mg/kg per day) both for 28 days. Treatment was considered successful if a bone marrow aspirate performed 1 month after the end of therapy did not detect parasites. Relapse was defined as the reappearance of parasites after an initial cure. RESULTS: An initial cure was attained in 29 of 44 patients (65.9%) randomly assigned to treatment with meglumine antimoniate and 28 of 45 (62.2%) randomly assigned to treatment with amphotericin B. The incidence of moderate to severe adverse events was similar in both groups. The patients treated with meglumine antimoniate had higher incidences of cardiotoxicity (14 versus 0%, P = 0.02) and chemical pancreatitis (30 versus 0%, P < 0.01). However, in the amphotericin B group, nephrotoxicity was more frequent (36 versus 5%, P < 0.01). There was no difference in survival or relapse-free interval according to the allocated group of therapy. CONCLUSION: Treatment of VL with meglumine antimoniate or amphotericin B was shown to have similar efficacy and toxicity rates in Spanish HIV-infected patients. The differences in the toxicity patterns could be useful in choosing one of these agents as first-line treatment.

AIDS-Related Opportunistic Infections↗
PubMed1999

[Gastrointestinal stromal tumors: prognostic value of DNA analysis with flow cytometry and of classical clinicopathologic parameters].

BACKGROUND: Biological behavior of gastrointestinal stromal tumours (GIST) is still difficult to predict. The aim of this study was to analyze the prognostic valve of DNA study by flow cytometry in addition to the classical clinicopathologic parameters. PATIENTS AND METHODS: 82 GIST were investigated to assess by multivariable analysis the prognostic significance of classical morphologic and clinical features and DNA flow-cytometric analysis. RESULTS: Features significantly correlated with bad prognosis were: pain, recurrences, metastasis, small intestine tumours, invasion of adjacent tissues, size > 6 cm, infiltrative pattern, high cellularity, high-grade of atypia, mitosis count > 2/50 high powered field, necrosis, DNA aneuploid-hyperploid or near-diploid, S and SG2M-phase of aneuploid/s population/s > 11% and average S-phase > 11%. Multivariable analysis showed that mitotic activity was the only independent variable indicating poor prognosis. CONCLUSIONS: In this series of GIST mitosis count was the only independent prognostic factor, being more important than flow-cytometric variables like DNA ploidy and cellular cycle values.

Adolescent↗
PubMed1999

Impaired mesenteric leukocyte recruitment in experimental portal hypertension in the rat.

Increased incidence of septic complications in human and experimental portal hypertension has been documented. Because development of an inflammatory response is essential in defense against infectious agents, the aim of this study was to assess leukocyte-endothelial cell interactions in an experimental model of portal hypertension. Intravital microscopy studies showed that under baseline conditions, leukocyte rolling, adhesion, and emigration in mesenteric venules were similar in control, sham operated (SO), and partial portal vein ligated (PPVL) rats. Compared with either control or SO rats, PPVL animals exhibited a markedly reduced recruitment of rolling, adherent, and emigrated leukocytes in response to leukotriene B(4) (LTB(4)) stimulation. Similarly, platelet-activating factor (PAF) superfusion, which induced a large increment in leukocyte rolling and adherence in control and SO rats, was without any effect in PPVL animals. Endothelial P-selectin expression in control rats, as measured by the double radio-labeled monoclonal antibody (mAb) technique, was not modified by LTB(4), but significantly increased in response to PAF. PPVL rats had a significantly lower expression of P-selectin after stimulation with PAF. Neutrophils isolated from PPVL rats exhibited increased L-selectin shedding and CD11b up-regulation in response to PAF and LTB(4), compared with neutrophils isolated from SO rats. These observations indicate that portal hypertension is associated with a defective inflammatory response, which is manifested as a decreased recruitment of rolling leukocytes, and subsequently reduced adhesion/emigration. This defect appears to result from a reduced endothelial P-selectin up-regulation and increased L-selectin shedding.

Animals↗
PubMed1999

Reperfusion-induced oxidative stress in diabetes: cellular and enzymatic sources.

Reactive oxygen metabolites (ROMs) have been implicated in the pathogenesis of the inflammatory response to ischemia/reperfusion (I/R), which is exacerbated in diabetes. This study revealed an increased (P < 0.01) ROMs production in mesenteric tissue (measured using the oxidant-sensitive fluorochrome dihydrorhodamine 123) after I/R in control and diabetic rats, with larger increments (P <0.0001) observed in the latter group, that was associated with an increased inflammatory response measured by intravital microscopy. Either xanthine oxidase inhibition, superoxide scavenging, ICAM-1 immunoneutralization, or blockade of platelet-activating factor or leukotrienes effectively reduced leukocyte recruitment and ROMs production in control and diabetic rats. Moreover, neutrophils from diabetic rats showed an enhanced production of ROMs in vitro in basal and stimulated conditions. We conclude that the oxidative stress during reperfusion is markedly enhanced in diabetes and this appears to result from increased leukocyte recruitment and a higher capacity of diabetic leukocytes to generate ROMs in response to stimulation.

Animals↗